Engine governor actuator



April 10, 1962 i M. F. STERNER ENGINE GOVERNOR ACTUATOR Filed Dec. 2,1957 INVENTOR. MELvlN ESTERNER BY W Y ATToRNE s tice vPatented Apr. 10,i962 3,023,847 ENGNE GOVERNOR ACTUATR Melvin F. Steruer, BlooxntieidHilis, Mich., assgnor to Holley Carburetor Company, Van Dyke, Mich., acorporation of Michigan Fiied Dec. 2, 1957, Ser. No. 699,970 6 Claims.(Cl. 12S- 103) The present invention relates generally to enginegovernors, and more specifically to means for actuating such governors.y

In the past engine governors for internal combustion engines usingcarbureting means have been provided which employed vacuum as the sourceof power for operating the speed control means, usually the throttle.Under certain conditions it becamerditiicult and costly to produce avacuum actuated governor having a low r.p.m. spread without at the sametime having a tendency to surge.

This problem has been magnified in the recent past by the fact that theautomotive industry is using a continually increasing percentage ofmultiple barrel carburetors. Because of this trend the vacuum availablefor operating the governor and other devices has diminished and theresulting forces are becoming insufficient for proper governor control.

With the foregoing in mind it is an object of the present invention toprovide a means for actuating a governor which may he designed to have avery low r.p.m. spread.

It is a further object of the present invention to provide a governor asdefined in the preceding paragraph characterized by the fact that anytendency to surge has been eliminated.

It is a further object of the present invention to provide a means foractuating the governor which is not dependent on a supply of vacuum.

It is a further object of the present invention to provide hydraulicfluid pressure actuated motive means for operating a speed controlmember, in combination with a source of hydraulic pressure variable inaccordance with engine speed.

More specifically, it is an object of the present invention to provide asource of hydraulic fluid under a Variable pressure dependent on enginespeed.

Still more specifically, it is an object of the present in vention toprovide, for use in conjunction with an internal combustion engine, asource of hydraulic liuid under a Variable pressure dependent on enginespeed, in combination with means to prevent supply of hydraulic uid at apressure less than that corresponding to a predetermined minimum enginespeed.

Other objects and features of the invention will become apparent as thedescription proceeds, especially when taken in conjunction with theaccompanying drawing, illustrating preferred embodiments of theinvention, where- FIGURE 1 is a schematic sectional View illustratingthe present invention.

FIGURE 2 is a sectional View illustrating a modification of the controlvalve.

FGURE 3 is a sectional view of a modified pressure supply unit.

In the embodiment of the invention illustrated in FIG- URE 1 there isprovided a unit for supplying hydraulic iluid under a variable pressuredependent on the speed of an internal combustion engine to becontrolled. The internal combustion engine includes the usual air intakepassage 12 associated with a carburetor for supplying fuel and having athrottle 14 associated therewith. The throttle 14 in the figure is shownin open position and is mounted for pivotal movement about a pivotsupport 16 and is provided with an operating arm j18 to which isconnected a rod 20 the opposite end of which is in turn secured to aflexible diaphragm 22 mounted in a housing indicated generally at 24 andcomposed of housing sections 26 and 28 between which the edges of thediaphragm 22 are clamped. The diaphragm divides the interior of thehousing 24 into chambers 30 and 32, the chamber 32 being a pressurechamber as will subsequently be described. The chamber 30 is vented toatmosphere as indicated at 34 and includes a compression spring 36biasing the diaphragm to the right as viewed in FIGURE 1 and hence in adirection to maintain the governor throttle plate 14 in positively openposition. It will be understood that suitable stop means (not shown) areprovided to limit opening movement of the throttle plate 14 to theposition shown. It will be apparent that when pressure is built up inthe chamber 32, the diaphragm 22 moves to the left thus moving thegovernor throttle plate 14 toward closed position. Y

In accordance with the present invention the means for supplyinghydraulic fluid to the chamber 32 comprises a unit indicated generallyat 40 including a housing portion 41 having a pumping chamber 42 thereinwhich receives a rotary impeller 44 connected to a drive shaft 46 whichin turn is connected to a rotating part of the internal cornbustionengine to be controlled, such for example as its cam shaft. 'Ihe shaft46 has an axially extending passage 48 communicating with radiallyextending passages 50 and these in turn communicate with an iniet port52 supplied with hydraulic fluid through a fitting 54 connected to aconduit 56. The impeller 44 includes a radially extending passage 58which communicates with the axially extending passage 48. Accordingly,as the shaft 46 is rotated by operation of the engine, pressure of thehydraulic uid in the chamber 42 is built up by centrifugal actionresulting from rotation of the impeller 44.

The housing portion 41 includes a recess 60 enclosed by a cover portion62 which clamps the edges of a ilexible diaphragm 64 thereby providingan internal pressure chamber 66. Between the flexible diaphragm 64 andthe bottom of the recess 60 there is provided a compression spring 68and the space containing the spring is Vented to atmosphere as indicatedat 70. The flexible diaphragm 64 carries a valve element 72 cooperablewith an outlet valve port 74. The pressure 0r pumping chamber 42 isconnected by a conduit or passage 76 with the pressure chamber 66.

The unit 40 is connected to a supply conduit 78 to the interior of thepressure chamber 32. In addition a fluid return line St) is providedextending from the pressure chamber 32 to the reservoir or other sourceof hydraulic fluid. A restriction S2 is providediin the return passage80 so as to establish some point of critical iiow.

With the foregoing construction in mind it will be observed that whenthe engine is started rotation is imparted to the shaft 46 and pressureof the hydraulic uid in the pressure chamber 42 increases as a result ofthe action of the impeller 44. This pressure is transmitted through thepassage 7 6 to the pressure chamber 66. However, escape of lluid underpressure is prevented since the valve 72 is on its seat and remains inclosed relation until the pressure within the pressure chamber 66reaches a value as determined by the strength of the spring 68 whichcorresponds to some predetermined engine speed. At this time the valve72 opens and hydraulic fluid under pressure is supplied to the pressurechamber 32 where it estab- Y lishes a force against the flexiblediaphragm 22 tending to close the governor throttle plate 14. Acontinuous liow of fluid takes place through the pressure chamber 312,this flow being restricted by the restriction 82 to maintain thepressure within the chamber 32 at a value dependent upon the pressuredeveloped by rotation of the impeller 44.

Accordingly, Abelow a predetermined engine speed, no

geraet? y apesar? pressure acts on the flexible diaphragm 22 and thethrottle plate 14 remains in full open position. However, at somepredetermined engine speed, the valve 72 opens and hydraulic fluid underpressure is admitted to the pressure chamber 32. The pressure within thepressure chamber 32 is dependent upon the pressure developed by theimpeller 44 and the amount of opening of the valve 72. The valve 72 maymove from fully closed to fully open position upon a very small changein pressure in the pressure chamber 66. The movement of the governorthrottle plate 14 is controlled by pressure in the chamber 32 overcomingthe effect of the spring 36 and accordingly, the throttle plate 14 maymove from fully open to fully closed position with an extremely smallr.p.m. spread. At the same time, the valve 72 has the elect ofpreventing a throttling action on the gear throttle plate 14 at speedsbelow the predetermined governed speed.

Referring now to FIGURE 2, there is illustrated a modication of thevalve which prevents supply of fluid from the unit at speeds below apredetermined minimum speed. In this figure there is illustrated acylindrical chamber 90 one end of which is vented to atmosphere asindicated at 92 and which contains a compression spring 94 engaging oneend of a piston 96 movable longitudinally of the chamber. Connected tothe chamber is a passage 9S corresponding to the passage 76 of FIGURE 1,and adapted to receive uid under pressure from a pumping chambercorresponding to the pumping chamber 42. At one side of the cylinder 90is a port 160 to which is connected a fluid supply passage 162corresponding to the passage 78 shown in FIGURE 1. It will be observedthat the piston 96 operates as a valve in conjunction with the port 100.Thus, as pressure supplied through the lpassage 98 builds up the pistonis moved upwardly against the spring 94 until the port 100 is uncoveredand thereafter, hydraulic fluid under pressure is supplied to the speedcontrol unit.

Referring now to FIGURE 3 there is illustrated a construction in which aseparate return conduit such as shown at 80 in FIGURE 1 is eliminated.In this embodiment of the invention the unit is self-contained andincludes a rst housing member 110 having a pumping chamber 112 thereinin which is mounted a rotary impeller 114 connected to a shaft 116 whichin turn is adapted to be connected to a rotating part of the engine suchfor example as its cam shaft. A uid supply passage 118 is provided whichcommunicates with the axially extending passage 120 in the shaft 116,the latter in turn communicating with the radially extending passages122 in the impeller. The unit includes a second housing assembly 124connected to the first member 110 and having a chamber 126 thereindivided by a exible diaphragm 128 into a pressure chamber 130 and asecond chamber 132 vented to atmosphere as indicated at 134. Thechambers 112 and 126 are connected by a passage 136 to deliver fluidfrom the chamber 112 to the pressure chamber 126. The chamber 126 isprovided with a passage 138 which leads to the speed control mechanism.Carried by the flexible diaphragm 128 is a valve 140 adapted to preventdelivery of hydraulic uid under pressure to the passage 138 untilpressure within the chamber 13) reaches a predetermined minimum value asdetermined by a compression spring 142 contained in the chamber 132.

Formed within the housing members 110 and 124 is a passage 144 extendingfrom the outlet passage 133 to the inlet passage 118. The passage 144 isprovided with a restriction 146 to establish a critical point of flow.It will of course be appreciated that the passage 144 and restriction146 correspond functionally to the external passage or conduit 86 andits restriction 82.

The unit illustrated in FIGURE 3 is thus adapted to provide a supply ofhydraulic fluid under a pressure which is determined by engine speedwhenever the engine speed is at or above a predetermined minimum speed.

Operation As the engine speed increases the shaft 46 or 116, which isdriven at some constant ratio to the engine speed, rotates the impeller44 or 114. This in turn causes the pressure of the tiuid in the chamber42 or 112 to increase and this pressure is transmitted to the chamber 66or 130. When the engine has reached sufficient speed and the pressurereaches some predetermined corresponding value the spring 68 or 142 willbe overcome by the pressure on the diaphragm 64 or 128. When thiscondition is reached the valve 72 or 140 opens and hydraulic huid underpressure then lows to the chamber 32. As the hydraulic uid reaches apoint of critical low through the restriction 82 or 146, pressure willcorrespondingly increase in the chamber 42 with an increase in enginespeed. As the pressure continues to increase the diaphragm 22 will bemoved to the left as seen in FIGURE l, against spring 36, and rotate thegovernor throttle plate 14 so as to limit the intake of combustiblemixture by the engine.

The drawing and the foregoing specification constitute a description ofthe improved engine governor actuator in such full, clear, concise andexact terms as to enable any person skilled in the art to practice theinvention, the scope of which is indicated by the appended claims.

What I claim as my invention is:

1. An engine speed governor for an internal combustion engine having amovable speed control member, a hydraulic fluid motor comprising anoperating pressure chamber having a movable wall, actuating meansconnected to said wall and adapted to move said speed control member ina speed reducing direction upon admission of pressure uid to saidchamber, a hydraulic pump adapted to be driven at a speed dependent onengine speed and to develop a pressure dependent on engine speed, saidpump having a single outlet port, a supply passage connecting the outletport of said pump to said chamber to deliver the entire output of saidpump to said chamber, a normally closed pressure responsive valve insaid passage, said valve having means responsive to the pressure ofhydraulic uid developed by said pump operable to open said valve at auid pressure corresponding to a predetermined engine speed, said passagebeing relatively unrestricted, and a relatively restricted exhaustpassage connected to said pressure chamber of the motor.

2. An engine speed governor for an internal com bustion engine having amovable speed control member, a hydraulic uid motor comprising anoperating pressure chamber having a movable wall, actuating meansconnected to said wall and adapted to move said speed control member ina speed reducing direction upon admission of pressure uid to saidchamber, a hydraulic pump adapted to be driven at a speed dependent onengine speed and to develop a pressure dependent on engine speed, saidpump having a single outlet port, a normally closed valve having apressure chamber, a valve element controlling discharge of fluid fromsaid pressure chamber, a resilient means operatively connected to saidvalve element and urging said valve element toward closed position, asubstantially unrestricted passage con necting the outlet port of saidpump to said pressure chamber of said valve to deliver the entire outputof said pump to said chamber of said Valve and effective to maintain thepressure of uid in said valve pressure chamber substantially at pumpdischarge pressure, a passage connecting the pressure chamber' of saidvalve and the operating pressure chamber of said fluid motor to deliverthe entire output of said pump to said motor when said valve is open,and a relatively restricted exhaust passage connected to said operatingpressure chamber.

3. An engine speed governor for an internal combbustion engine having amovable speed control member, a hydraulic uid motor comprising anoperating pressure chamber having a movable wall, actuating meansconnected to said wall and adapted to move said speed control member ina speed reducing direction upon admission of pressure uid to saidchamber, a hydraulic pump adapted to be driven at a speed dependent onengine speed and to deliver hydraulic fluid at a pressure dependent onengine speed, a normally closed valve having a pressure chamber, a valveelement controlling discharge of fluid from said pressure chamber,resilient means operatively connected to said valve element and urgingsaid valve element toward closed position, said pump having a singleoutlet port, a substantially unrestricted passage connecting the outletport of said pump to said pressure chamber of said valve to deliver theentire output of said pump to said pressure chamber of said valve andeiective to maintain the pressure of fluid in said valve pressurechamber substantially at pump discharge pressure, a substantiallyunrestricted passage connecting said valve and the operating pressurechamber of said uid motor, and a relatively restricted exhaust passageconnected to said operating pressure chamber.

4. A hydraulic engine speed governor for an internal combustion enginehaving a movablespeed control member, a hydraulic motor connected tosaid member and operable when supplied with hydraulic uid under pressureto move said member in speed reducing direction, a.

housing having a pump chamber therein, an inlet passage connected tosaid pump chamber, a centrifugal pump rotor in said chamber, means forconnecting said rotor to the engine for rotation thereby at a speeddependent on engine speed to maintain hydraulic fluid in said pumpchamber at a pressure dependent on engine speed, a valve chamber in saidhousing having a movable Wall therein, said pump having a single outletport, a substantially unrestricted pump outlet passage connecting saidpump outlet port and said valve chamber for delivery of the entireoutput of said pump to said valve chamber, a valve port in said valvechamber, a valve connected t said movable Wall for actuation thereby,resilient means urging said valve to closed position and yieldable toopen said valve upon development of a predetermined elevated pressure ofhydraulic fluid in said valve chamber, an unrestricted supply passageconnecting said valve chamber to said motor, and a restricted returnpassage located downstream from said valve to establish a critical ilowpoint and to provide for delivery of hydraulic fluid to said motor whensaid valve is opened at pressure substantially equal to the pressure insaid pump chamber and said valve chamber.

5. A governor as dened in claim 4 in which said rehydraulic uid motorcomprising an operating pressure chamber having a movable Wall,actuating means connected to said wall and adapted to move said speedcontrol member in a speed reducing direction upon attainment of apredetermined pressure in said operating pressure chamber, a centrifugalhydraulic pump adapted to be driven at a speed dependent on engine speedand to develop a pressure dependent On engine speed, said pump having asingle outlet port, a normally closed valve having a pressure chamberincluding a movable Wall subjected at one side to hydraulic pressureWithin the pressure chamber of said valve and at the other side toatmospheric pressure, resilient means connected to said Wall to biassaid wall in a direction opposing movement induced by an increase inpressure Within the pressure chamber of said valve, the pressure chamberof said valve having a single inlet port and a single outlet port, avalve element connected to said movable wall controlling the singleoutlet port of the pressure chamber of said valve and movable in openingdirection upon attainment of a predetermined pressure Within thepressure chamber of said valve, a substantially unrestricted passageconnecting the single outlet port of said pump to the single inlet portof the pressure chamber of said valve, a substantially unrestrictedpassage connecting the single outlet port of the pressure chamber ofsaid valve to the operating pressure chamber of said motor, and arestricted exhaust passage connected to the operating pressure chamberof said motor. v

(Addition to No. 941,544)

